TK83854DIMG

TK83854 HIGH POWER FACTOR PREREGULATOR FEATURES s s s s s s Control Boost PWM to 0.99 Power Factor Limit Line Current Distortion to < 5% Worldwide Operation without Switches Feed-Forward Line Regulation Low Noise Sensitivity Pin Compatible with UC2854, and UC3854 (Licensed Source) FEATURES (CONT.) s s s s s Low Start-Up Supply Current Fixed-Frequency PWM Drive Low-Offset Analog Multiplier/Divider 1 Amp Totem-Pole Gate Driver Precision Voltage Reference DESCRIPTION The TK83854 family of integrated circuits provide active power factor correction for power systems that otherwise would draw non-sinusoidal current from sinusoidal power lines. These parts implement all the control functions necessary to build a power supply preregulator capable of optimally using available power-line current while minimizing line-current distortion. To do this, the TK83854 contains a voltage amplifier, a precision analog multiplier/ divider, a current amplifier, and a fixed-frequency PWM. In addition, the TK83854 contains a power MOSFET gate driver, 7.5 V reference, line anticipator, load-enable comparator, low supply detector, and overcurrent comparator. The TK83854 family uses average current-mode control to accomplish fixed-frequency current control with stability and low distortion. Unlike peak current-mode control, average current control accurately maintains sinusoidal line current without slope compensation. The TK83854's high reference voltage and high oscillator amplitude minimize noise ...